Also, please coordinate with the Gwenview team before doing such large changes in the future, e.g. by opening a Diff on Phabricator.

(In particular, this makes merging stable to master more difficult for us for the whole lifetime of 18.08 and increases compile times when switching branches. As such, it's preferable to defer such changes to the time window between the last stable release (18.08.3) and the beta of the next major release (18.12).)